hi does any one know if you can hear the diaphram moveing when you suck on the vacume pipe . .
i hear nothing. . could this be a problem ,thanks .

No, I don't remember it being noisy. In principle the diaphragm doesn't move it simply flexes to reduce/increase the pressure of the ball valve on the seat. This regulates the pressure.

Good things:
a. no noise
b. holds vacuum when you suck on it.
c. pressure fluctuates according to vacuum "load"
d. holds fuel pressure at 36psi and increases to 42? as you apply vacuum.

Things to look for:
a. fuel pressure drops immediately the fuel pump stops. The system should hold the pressure for at least few minutes.
b. fuel leaks internally through the vacuum tube when you suck on it.
c. the fuel pressure must be 36 psi with no vacuum applied.

Thanks again ned . . have yourself a V.B.